In wireless communication networks, such as LTE or LTE advanced, transmissions may be organized into radio frames, e.g. comprising equally-sized sub-frames. Resource allocation, e.g. in LTE, may described in terms of resource blocks (RB), where a resource block may corresponds to one slot in the time domain and a number of subcarriers in the frequency domain. A pair of two resource blocks, adjacent in time, may be referred to as a resource block pair, also denoted as Transmission Time Index or Transmission Time Interval, TTI.
Packet data latency is one of the performance metrics that vendors, operators and also end-users (via speed test applications) regularly measures. Radio resource efficiency could be positively impacted by latency reductions. Lower packet data latency could increase the number of transmissions possible within a certain delay bound; hence higher Block Error Rate (BLER) targets could be used for the data transmissions freeing up radio resources potentially improving the capacity of the system.
One problem with conventional wireless communication networks is the required transport time of data and control signaling, e.g. due to the duration of a TTI.
A further problem with conventional wireless communication networks is when a wireless device is served by one or more cells or carriers involved in Carrier Aggregation, CA, or dual connectivity, DC, is that an unnecessary large timing misalignment margin is used. This leads to increased latency. The timing misalignment margin may be represented by a maximum received time difference, MRTD, parameter. The timing misalignment margin is intended to compensate for relative propagation delay, e.g. the difference of propagation delay between the MeNB and the SeNB, transmission timing difference due to synchronization levels between antenna connectors of the MeNB and the SeNB, and delay due to multipath propagation of radio signals. In other words, the MRTD specifies the maximum timing misalignment between the two signals that the UE shall be or is able to receive when operating in CA/DC, and that may be a result of difference of propagation delay between the MeNB and the SeNB, transmission timing difference, e.g. due to synchronization levels between antenna connectors of the MeNB and the SeNB, and delay due to multipath propagation of radio signals.
Yet a further problem with conventional wireless communication networks is that the specified maximum receive timing difference is suitable for longer TTI duration.
Yet a further problem with conventional wireless communication networks is that they do not support the scenario when different TTI durations or timing misalignment margin is used in different cells or carriers involved in a CA (or DC) operation.
Thus there is a need to provide a solution which mitigates or solves the drawbacks and problems of conventional solutions.